Few-layer MoSe? possessing high catalytic activity towards iodide/tri-iodide redox shuttles.

ABSTRACT: Due to the two-dimensional confinement of electrons, single- and few-layer MoSe? nanostructures exhibit unusual optical and electrical properties and have found wide applications in catalytic hydrogen evolution reaction, field effect transistor, electrochemical intercalation, and so on. Here we present a new application in dye-sensitized solar cell as catalyst for the reduction of I?(-) to I(-) at the counter electrode. The few-layer MoSe? is fabricated by surface selenization of Mo-coated soda-lime glass. Our results show that the few-layer MoSe? displays high catalytic efficiency for the regeneration of I(-) species, which in turn yields a photovoltaic energy conversion efficiency of 9.00%, while the identical photoanode coupling with "champion" electrode based on Pt nanoparticles on FTO glass generates efficiency only 8.68%. Thus, a Pt- and FTO-free counter electrode outperforming the best conventional combination is obtained. In this electrode, Mo film is found to significantly decrease the sheet resistance of the counter electrode, contributing to the excellent device performance. Since all of the elements in the electrode are of high abundance ratios, this type of electrode is promising for the fabrication of large area devices at low materials cost.

SUBMITTER: Lee LT 

PROVIDER: S-EPMC3924216 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature